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ground wires (the shielding layer of communication cables) to
form a grounding system. See below. When measured with a
clamp meter, its equivalent circuit is as follows:
Where: R1 is the predicted ground resistance.
R0 is the equivalent resistance of the grounding resistances of
all other towers in parallel.
Although, from the strict grounding theory, due to the existence
of the so-called "mutual resistance", R0 is not a parallel value in
the usual electrotechnical sense (it will be slightly larger than
the parallel value in the electrotechnical sense), but, since the
grounding hemisphere of each tower is much smaller than the
distance between towers, and after all, the number of grounding
points is large, R0 is much smaller than R1. Therefore, it is
reasonable to assume R0=0 from an engineering point of view.
In this way, the resistance we measure should be R1.
Contrasting experiments with traditional methods in different
environments and occasions have proved that the above
assumptions are completely reasonable.
